• Membrane and Water Treatment
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• v.13 no.2
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• pp.85-95
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• 2022

Tetrachloroethylene (PCE) and trichloroethylene (TCE), critical pollutants to human health and groundwater ecosystems, are managed by groundwater quality standards (GQS) in South Korea. However, there are no GQSs for their by-products, such as cis-dichloroethylene (DCE) and vinyl chloride (VC) produced through the dechlorination process of PCE and TCE. Therefore, in this study, we monitored PCE, TCE, cis-DCE, and VC in 111 national groundwater wells for three years (2016 to 2018) to evaluate their distributions, a biological dechlorination possibility, and human risk assessment. The detection frequency of them was 30.2% for PCE, 45.1% for TCE, 43.9% for cis-DCE and 13.4% for VC. The four chlorinated compounds were commonly detected in 21 out of 111 wells. In the results of statistical analysis with 21 wells data, DO and ORP also had a negative correlation with four organic chlorinated compounds, while EC and sulfate has a positive correlation with the compounds. This indicates that the 21 wells were relatively met with suitable environments for a biological dechlorination reaction compared to the other wells. Finally, cis-DCE had a non-carcinogenic risk of 10^-1 and the carcinogenic risk of VC was 10^-6 or higher. Through this study, the distribution status of the four chlorinated compounds in groundwater in South Korea and the necessity of preparing plans to manage cis-DCE and VC were confirmed.

• Korean Journal of Food Science and Technology
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• v.43 no.1
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• pp.6-11
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• 2011

Vinyl chloride (VC) and vinylidene chloride (VDC), which may be present in poly(vinyl chloride) (PVC) and poly(vinylidene chloride) (PVDC) food packaging, were analyzed by using a headspace-gas chromatograph (GC)/mass spectrometer (MS) equipped with a PLOT Q column. 1-Chloropropane (1-CP) was used as an internal standard. The determinations of VC and VDC were carried out by monitoring the characteristic ions for each compound: m/z=61, 62, 64 and m/z=61, 96, 98, respectively. The method validated in this study can be suitable for the compliance test of EU regulation. Among 103 food packaging samples, VC and VDC were not detected, except in one PVDC food package. However, the detected level of VDC in the sample was below the EU regulatory specific limitation.

• Korean Journal of Weed Science
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• v.14 no.4
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• pp.291-297
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• 1994

Seedlings of eight varieties of tomato were treated on the soil surface by each six application rate (0 to 5g ai/ha) of herbicide quinclorac. Percent of control in plant height at 7 days after treatment ranged from 69% to 81% at 5g ai/ha application of quinclorac. At 28 days after treatment those of (2-26)*836038 and (TR*VC8-1)-1-2F4 were 88% and 89%, respectively. However, those of other six varieties except former two varieties were 61% to 68%. The variations of percent of control in shoot dry weight among eight varieties were larger than those in plant height. Those of (2-26)*836038 and (TR*VC8-1)-1-2F4 were also higher than those of other six varieties at 4 - 5g ai/ha application of quinclorac.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.23-23
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• 2003

Chestnut blight, caused by Cryphonectria parasitica, is the most destructive disease of American and European chestnut trees. A total of 672 C prasitica was isolated from blight lesion on chestnut twigs, which were collected from major chestnut plantations all over Korea in 1999. Isolation rates were over 30% in Kyunggj-, Kyongnam-, and Chonnam-do. The highest isolation rate was 37.4% and recorded in Kyongnam-do. On the other hand, Chonbuk-do had the lowest isolation rate as 13.5%. In grouping of C parasitica by colony shape and color, yellow colony with irregular margin were the most dominant colony type with a frequency of 65.2%. When the 672 isolates were inoculated on the chestnut twigs, 380 isolates (56.5%) caused lesions larger than the standard virulent isolate EP155-2, while 158 isolates (23.4%) caused smaller lesions than the standard hypovirulent isolate UEP-1. In Bavendamm test that determines phenol oxidase activity, 97.1% of all the isolates resulted the same or darker discoloration than EP155-2, and only 12.2% resulted the same or lighter discoloration than UEP-1. In the vegetative compatibility (VC) tests, total 670 isolates were divided into 121 VC groups (VCGs). Kyongnam-, Chonnam-, and Chungnam-do, the three principal chestnut plantation area, had 49, 33, and 27 VCGs, respectively. Among the VCGs, the biggest VCG, KR-VC104, was composed of 164 isolates and the second biggest VCG had 62 isolates. But, 64 of 121 VCGs consisted of sole member. More than 65.8% of KR-VC104, was isolated from the three provinces, Kyongnam-, Kangwon-, and Chungbuk-do. In KR-VC104, 62.8%, 59.1%, and 85.9% of the isolates looked like virulent in colony type, pathogenicity test, and Bavendamm test. In ds-RNA detection tests using cellulose chromatography, 77 of total 650 isolates were ds-RNA positive and detected ds-RNA segments were approximately 12kb, 3kb, 2.7kb, 2kb, and 1.8kb in size. Among the 77 isolates, 46 isolates had 12kb and 25 isolates had 12kb and 2.7kb. Other 6 Isolates had small ds-RNA segments. Kyongnam-, Chonnam-, and Chungnam-do had 43, 16, and 5 ds-RNA positive isolates, respectively. Among the 121 VCGs, only 29 VCGs had ds-RNA positive isolates.(중략)

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.41 no.1
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• pp.73-82
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• 2004

As a new service category to better support TCP traffic in ATM networks, the Guaranteed Frame Rate (GFR) service category aims to support minimum cell rate guarantee, fairly distribute available bandwidth while keeping the simplicity of Unspecified Bit Rate (UBR). In this paper, we proposed a buffer management scheme which uses the per-VC accounting of single FWO queue and capable of supporting both GFR.1 and GFR.2 conformance definition. The proposed buffer management deal with GFR.1 and GFR.2 conformance definitions differentially by controlling the number of CLP=0 cell and CLP=1 cell which are occupying buffer space. The simulation results show that our proposed scheme satisfies the requirements of GFR services as well as improves total fairness index and each conformance definition fairness index.

• Journal of the Korean Society of Physical Medicine
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• v.18 no.2
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• pp.115-123
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• 2023

PURPOSE: This study examined the effects of combined conventional exercise therapy plus respiratory exercise program with combined conventional exercise therapy plus aqua exercise program in the pulmonary function of subacute stroke patients. METHODS: The respiratory exercise program group underwent inspiration and expiration training using the Threshold IMT and Threshold PEP three days per week for four weeks. The aquatic exercise program group had aquatic aerobics, halliwick, and bad ragaz ring training three days per week for four weeks. Before and after the experiment, Pony fx was used to examine the FVC, FEV1, FEV1/FVC, VC, and MVV. RESULTS: Significant improvement was found after the experiment in the FVC. FEV1, VC, MVV, excepting FEV1/FVC, of the pulmonary function in the aquatic exercise program group. After the experiment, significant improvement was found in FVC, FEV1, FEV1/FVC, VC, and MVV of pulmonary function in the respiratory rehabilitation therapy group. No significant difference in FVC, FEV1, FEV1/FVC, VC, and MVV of pulmonary function was observed in the inter-group comparison. CONCLUSION: Significant improvement was found after the experiment in both the aquatic exercise program group and the respiratory exercise program group. No difference in pulmonary function was noted in the inter-group comparison. Therefore, combining general exercise therapy and an aquatic or respiratory exercise program is expected to be effective for the pulmonary function of acute stroke patients. These results are expected to provide basic data to help research intervention of aquatic and respiratory exercise programs for subacute stroke patients.

• Journal of the Korean Electrochemical Society
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• v.15 no.1
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• pp.19-26
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• 2012

SEI (solid electrolyte interphase) layers are generated on a graphite negative electrode from three different electrolytes and low-temperature ($-30^{\circ}C$) charge/discharge performance of the graphite electrode is examined. The electrolytes are prepared by adding 2 wt% of vinylene carbonate (VC) and fluoroethylene carbonate (FEC) into a standard electrolyte solution. The charge-discharge capacity of graphite electrode shows the following decreasing order; FEC-added one>standard>VC-added one. The polarization during a constant-current charging shows the reverse order. These observations illustrate that the SEI film resistance and charge transfer resistance differ according to the used additives. This feature has been confirmed by analyzing the chemical composition and thickness of three SEI layers. The SEI layer generated from the standard electrolyte is composed of polymeric carbon-oxygen species and the decomposition products ($Li_xPF_yO_z$) of lithium salt. The VC-derived surface film shows the largest resistance value even if the salt decomposition is not severe due to the presence of dense film comprising C-O species. The FEC-derived SEI layer shows the lowest resistance value as the C-O species are less populated and salt decomposition is not serious. In short, the FEC-added electrolyte generates the SEI layer of the smallest resistance to give the best low-temperature performance for the graphite negative electrode.

• The Journal of the Acoustical Society of Korea
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• v.21 no.2
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• pp.160-166
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• 2002

In this paper, we implement a new vocabulary-independent speech recognition system that uses CV, VCCV, VC recognition unit. Since these recognition units are extracted in the trowel region of syllable, the segmentation is easy and robust. And in the case of not existing VCCV unit, the units are replaced by combining VC and CV semi-syllable model. Clustering of vowel group and applying combination rule to the substitution model in the case of not existing of VCCV model lead to 5.2% recognition performance improvement from 90.4% (Model A) to 95.6% (Model C) in the first candidate. The recognition results that is 98.8% recognition rate in the second candidate confirm the effectiveness of the proposed method.

• The Journal of Korean Physical Therapy
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• v.26 no.3
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• pp.169-174
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• 2014

Purpose: This study demonstrated a postural alignment exercise as conservative management strategy for a woman with excessive thoracic kyphosis presenting decreased chest function, and reports its results. Methods: A 21-year-old woman with thoracic kyphosis presenting limited chest function. The exercise program underwent for 30 min in the intervention phase, which consisted of exercises to improve the strength of back extensor and to stretch anterior chest region. Outcome measures comprised the severity of thoracic kyphosis and chest function (vital capacity [VC], forced expiratory volume in a second [FEV1], and chest expansion length). Results: The thoracic kyphotic angle decreased by 23.6% ($9.38^{\circ}$) and 25.4% ($10.58^{\circ}$) in the intervention and follow-up phases respectively. Also, chest function was improved in the intervention (VC: 3.7% [$0.10{\ell}$], FEV1: 17.1% [$0.39{\ell}$], and chest expansion length: 17.1% [0.96 cm]), and the improvement was maintained during the follow-up phase (VC: 4.8% [$0.13{\ell}$], FEV1: 17.1% [$0.39{\ell}$], and chest expansion length: 64.3% [1.81 cm]). Conclusion: These findings suggest that the postural alignment exercise was favorable for improving chest function of a woman with thoracic kyphosis.

• Journal of International Academy of Physical Therapy Research
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• v.6 no.2
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• pp.878-883
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• 2015

The purpose of this study compared the ability of feedback breathing training (FBT) and balloon blowing training to enhance the breathing of elderly people. The subjects were randomly and evenly divided into a feedback breathing training group (FBTG) and a balloon blowing training group (BBTG). Each group trained 3 times a week for 4 weeks, with the training suspended during the last 2 weeks. Pulmonary function measurements were obtained before the test and 2, 4 and 6 weeks after the test: forced vital capacity (FVC), forced expiratory volume at one second (FEV1), FEV1/FVC, peak expiratory flow (PEF) and vital capacity (VC). A repeated-measures ANOVA was conducted for the significance test. The FBT resulted in a significant increase in the FVC, FEV1/FVC, PEF, and VC of the elderly smokers after 4 weeks and a significant decrease in the FVC, FEV1/FVC, and PEF after 6 weeks. The BBT resulted in a significant increase in the FVC, FEV1, FEV1/FVC, PEF, and VC of the elderly smokers after 4 weeks and a significant decrease in the FVC, FEV1/FVC, and PEF after 6 weeks. In conclusion, An at home breathing rehabilitation program, in addition to balloon blowing, could increase the breathing performance of elderly people.